Additional meeting and call-related features and issues within Microsoft Teams for business
I've got this exact same issue.
I get Windows OS system sounds and Teams App sounds via standard notification sounds and calls. But the meeting has zero audio. Test call returns audio as expected.
Checked Teams admin console, it states audio for the meeting as complete with no error codes.
I'm wondering if this is a malfunction in a specific app setting:
Turn on new meeting experience (new meetings and calls will open in separate windows. Requires restarting Teams.)
Maybe it's not switching audio to the meeting window when it's opened as a new window.
For everyone having this issue with the app having audio but not in the meeting itself, is that setting turned on or off when this happens?